The present invention relates to telephone systems, and in particular to computer communications over telephone systems.
Telephone systems were initially, and are now predominantly analog systems. Computers are practically by definition digital devices. In order to transfer data from one computer to another computer using an analog telephone system, the digital signals from the computer are converted into analog signals that are transferable over an analog telephone system. The device for converting the digital and analog signals is known as a modem.
As computers have evolved, new ways of communicating between computers has also evolved. One new way of computer communication is by infrared (IR) electromagnetic waves. Infrared communication has features that are advantageous in specific circumstances. Infrared communication does not require the connection of electrical cables, but is disadvantageous because it requires a line of sight between the transmitter and receiver, and infrared communication requires relatively close distances between the transmitter and receiver. Infrared communication is often used in notebook computers for communicating with a docking station or another notebook computer, or other handheld computing devices. Infrared communication is desirable in these circumstances because the units are usually very close together, and no physical cable needs to be provided or connected. However for long distances computer communications, physical electrical cables are preferred.
It is a primary object of the present invention to provide a telephone system that can be easily connected to a computer for long distance computer communications.
The present invention accomplishes this object by providing a telephone set of a telephone system with an infrared interface. This infrared interface is able to communicate with an infrared port on the computer. The computer is configured to send data to the infrared port, and receive data from the infrared port, in the same manner as if the computer was sending and receiving data over a telephone system. The telephone circuitry in the telephone system receives the infrared data and converts the infrared data into a format for transmitting across the telephone system.
In a preferred embodiment, the computer is configured to use the infrared port as it would use a serial port with an external modem. The telephone circuitry in the telephone system operates as an external modem receiving serial data via the infrared interface. This is very convenient especially for portable computers which need a temporary long distance communication connection. The infrared port of the computer only needs to be arranged within a line of sight of the infrared interface of a telephone set of the present invention. The local computer does not require any other physical connections or structures. The software in the local computer can be easily configured to use the infrared port as a serial connection with an external modem. Many operating systems for computers, especially personal computers, can be automatically configured when devices are added. The infrared interface on the telephone set could be programmed to emit a modem identifying signal, and the local computer could automatically recognize that a modem is available through the infrared port. In the alternative, the local computer could be specifically told that an external modem is present through the infrared port. The exact configuration of the local computer to use the infrared port as a serial connection to an external modem depends on the type of operating system used by the local computer and is within the ability of those persons skilled in the art of computer operating systems.
The local computer can then be easily removed from a position for long distance communication and moved to another position according to the needs of the local computer user. The connection and disconnection of electrical cables is therefore eliminated.
Also the need for a modem in the local computer is also eliminated. This is very advantageous because the cost, weight, volume and power consumption of a modem is also eliminated. The infrared port of the local computer is able to perform two functions which makes the infrared port more valuable.
A more important benefit of using the IR port to connect to a telephone system is that the specific structure required for the signal conversion resides in the telephone circuitry of the telephone system. There are many different types of telephone systems, and many with their own signal format. Probably the largest and most common is known as the Public Switched Telephone Network (PSTN). This is the telephone systems that connects the individual residences and businesses in a community. As described previously, this system is predominantly analog and requires a modem to be able to transfer computer data. New digital services are being provided by the PSTN, such as DSL and ISDN. These new digital services do not require an analog modem, but instead require a different type of converter. Furthermore, many organizations had their own private telephone system for communicating within the organization, and between the organization and the PSTN. These private telephone systems are known as Private Branch eXchanges (PBX). There are many different types of PBX""s available, with many different types of signal formats for transferring the voice data between the telephone sets of the PBX.
For a computer to communicate over a telephone system, it is necessary for the computer to know what type of signal format the telephone system is using. With all the different types of signal formats, such as PSTN analog, DSL, ISDN, and the individual proprietary formats for PBX""s, having a computer/telephone converter for all of the possible signal formats is prohibitively expensive. Very often an organization will run a PSTN analog line separate from the PBX lines in order to provide a computer with long distance communication.
With the present invention, the telephone set inherently knows the signal format of the telephone system to which it is connected. Therefore the telephone circuitry only needs to provide one computer/telephone converter. This in combination with the local computer only requiring an infrared port, is a great reduction in cost and a great increase in versatility. The user of the local computer no longer needs to determine the signal format of the telephone system and then try to obtain the proper computer/telephone converter. The computer/telephone converter is built into the telephone circuitry of the telephone system. The computer user can then easily and quickly connect to any telephone system using the present invention.
When the present invention is incorporated into a PBX which is connected to a PSTN, the telephone set has a converter for converting the data from the infrared interface into the signal format of the PBX. The telephone set also directs this computer data to the PBX hub for connection to the PSTN. The PBX hub then has another converter for converting from the PBX format to the PSTN format. This type of converter is similar to a modem.
A PBX can also be used to connect a plurality of computers in an organization to form a Local Area Network (LAN). This is described in U.S. patent application Ser. No. 09/203,542 filed Dec. 1, 1998. This is known as a PBX/LAN network, and can also take advantage of the present invention. In a further embodiment of the present invention, the infrared interface of the telephone set can receive data from the local computer for transmission to the other computers on the LAN. The telephone set can either be manually switched to send data from the IR interface to the modem in the PBX hub, or to send data from the IR interface to the LAN. The local computer is also either manually or automatically switched to transfer modem data or LAN data through the IR port. This is especially useful for members of the organization which use portable computers and need to repetitively connect and disconnect from the LAN of the organization. These highly mobile members of the organization can rapidly connect and disconnect from the LAN, and can also rapidly connect and disconnect from the PSTN. These uses also do not need to only connect at one particular location, but the IR interface of the telephone sets allows these uses to connect wherever an IR telephone set is present. The mobility and versatility of computers and the PBX/LAN network is increased and allows an organization greater opportunities.